So Miu is cosplaying as Onpu because she has fans, Ritsu is cosplaying as Aiko because she's the energetic tomboy, Nodoka is Hazuki because of the glasses and because she's a straight A student, Yui is Doremi because she's the clumsy protagonist, Ui is Pop because she's the protagonist's little sister, Azusa is Hana because she's small and younger and has long twintails (I guess), Tsumugi is Momoko because of her eyebrows. It all kinda makes sense.
But I'm still unsure about miss Sawako. Is she Majorika in human form?